Improvement in saw-mill head-blocks



tached, the pinions i.

UNIT D STATES PATENT OFEIcE.

B. DEXTER WHITNEY, OF GARDINER, MAINE.

IMPROVEMENT IN SAW-MILL HEAD-BLOCKS.

Specification forming part of Letters Patent No. 199,386, dated January22, 1878; application filed November 20, 1877.

To all whom it may concern:

Be it known that I, B. DEXTER WHITNEY, of Gardiner, in the State ofMaine, have invented certain new and useful Improvements in Saw-Mills;and I do hereby declare that the following is a full, clear, and exactdescription thereof, which will enable others skilled in the art towhich it appertains to make and use the same, reference being had to theaccompanying drawings, and to letters of reference marked thereon, whichform a part of this specification.

Figure 1 is a top plan. Fig. 2 is an end view. Fig. 3 is a top section.Fig. 4 is a detail to show the tracks.

Same letters show like parts.

The object of my invention is to provide a machine for setting logs forsawing. The devices are to operate in such way as to move up the lumberafter each board or piece is cut off, so that another of the desiredthickness can be removed.

a is the bottom frame, which moves to present the log to the saw. bisthe top frame, carrying my improvements. The bottom frame is furnishedwith the tracks 0, bolted to it and across it. d are slides attached tothe under side of I), to move on the tracks 0. The log rests on thetracks '0. It is pushed along on these tracks as boards orpieces aresawed. off in a direction across the frame a, and with the tracks 0.

It remains to describe how this operation, in which my inventionconsists, is effected. Within the frame b are the moving racks e andbelts f, moving horizontally within the frame. spaces to fit over theteeth of the wheels g, rigidly set on upright short shafts h, whichshafts have, at their lower ends, rigidly at- The shafts it have bearings j. k is an upright lever-shaft, with a pinion, l, at the lower end,working into the moving racks e, and by which they are moved with thebelts f, &c. This shaft 70 is supported by The belts are so-made as tohave a frame, m, rising from the frame I). n is a pawl on the top end ofk, set on an arm, 0, projecting horizontally out from k. This pawl has acatch, 10, to hold it when disengaged from the ratchet q, rigidly set onthe top end of k. The pawl is pivoted at r, and has a joint at 8, formedby the end of one part workin g into a notch in the end of the otherpart, as illustrated. Working into this slot or notch is a spring, whosetendency is to keep the bifurcations c of the pawl disengaged from theratchet q, and which will throw them out of the ratchet when the forceof the leverage of n is taken away. By turning the arm in one directionone of the bifurcations s will engage i-nto the ratchet q, and then, bymoving the arm 0 backward and forward, the frame I) is caused to slidein one direction. When the other bifurcation c is engaged the oppositemovement of b is the result. This motion of the frame I) is immediatelyproduced by the pinions 2' working in the racks w on the sides of two ofthe tracks 0. Thus a movement in either direction of the frame I) isobtained, and such movements of the lumber or log sidewise can be givenas are necessary.

It will be, of course, understood that the log or lumber is properlyheld or dogged to the upper moving frame I).

What I claim as my invention, and desire to secure by Letters Patent,is- The combination, with the two frames at and b, of the tracks 0,slides d, moving racks e, belts f, wheels 9, and shafts, pinions i,racks w, upright shaft k, pawl n, with parts 0 r s 'v t u p, ratchet q,and pinion l, as herein described. I In testimony that I claim theforegoing as my own I affix my signature in presence of two witnesses.

B. DEXTER WHITNEY.

-Witnesses:

WM. S. BROWN, G. W. OOLB RN.

